why does my Ford Mustang S550 (2015-2023) engine light come on after filling gas

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Gas Cap

• Sub-steps:
  1. Remove the gas cap and inspect it for cracks or wear.
  2. If damaged, replace it with a new one.
• Tools Required: None specifically for this step.

3. Check and Repair EVAP System

• Sub-steps:
  1. Locate the EVAP purge valve and disconnect the electrical connector.
  2. Remove the valve and test it with a multimeter to ensure it operates correctly.
  3. If faulty, replace the purge valve.
  4. Inspect the charcoal canister for cracks and replace if necessary.
• Tools Required: Multimeter, socket set.

4. Inspect Fuel Lines and Filler Neck

• Sub-steps:
  1. Visually inspect the fuel lines for any cracks or leaks.
  2. Check the fuel filler neck for rust or damage.
  3. Replace any damaged components as necessary.
• Tools Required: Socket set, screwdriver.

5. Test Fuel Pressure

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the "ON" position without starting the engine to check the pressure.
  3. Compare the reading to the manufacturer's specifications (typically around 30-50 PSI for most vehicles).
  4. If the pressure is low, consider replacing the fuel pump.
• Tools Required: Fuel pressure gauge.

6. Reassemble and Test

• Sub-steps:
  1. Reconnect all components and ensure everything is secure.
  2. Reconnect the negative battery terminal.
  3. Start the engine and monitor for any abnormal sounds or warning lights.
• Tools Required: None specifically for this step.